The first enclosure at Winchester was built in 150 BC during the Iron Age, at the same time that a trading center was established. In 70 AD the Romans arrived and called Winchester "Venta Belgarum - marketplace of the Belgae," a regional capital.
Then in 410 AD the Romans left and the capital collapsed. In 648 AD the first minster was founded as Christianity came to Winchester, now called the old minster. After the City's surrender to William the Conqueror in 1066, he started to build the present cathedral. The history of what was once the capital of England is so great it would need two lifetimes to even learn it all!